Grinding-machine.



J. MILLER, Jn. GRINDING mofimn. APPLICATION IIL BD JAN. 29, 1909.

' Patented 099191909.

wh m/91 inerals of reference wheel or disk.

rm .1: Arne PATEN 'BOHN MILLER, 33., OF IBELOIT, VIISCONSIN, ASSIGNOR TO KATHLEEN M. H. BESLY, OF CHICAGO, ILLINOIS.

onmnINe-Mnbnmn of lVisconsin, have invented certain new and and 1, JOHN MILLER, that the following is description thereof, reference being'had to the accompanying drawings, and to the numarked form a part of this specification. I

This invention relates to improvements in grinding or olishing machines and more especially to at surface grinding machines, or what are generally known as disk grinders.

The invention relates more to a work holding attachment, which is proivided with means for backing or supporting the object to be ground, adapted to maintain the same in J r., do hereby declare particularly The invention inafter set forth and more pointed out in the'appended claims.

The holding attachment may be used in connection with the improved feed table described and shown in my prior application for Letters Patent No. 372,412, filed May 1907, parts of which are shown in the acflompanying drawings, inwhich,

igure 1 is a side view showing my improved work supporting device in place upon a grinding machine table. plan view of the feed table showing the means for advancing the said feed table toward the grinding wheel. Fig. 3 is a vertical section taken upon line 3-3 of Rig. 1. Fig. 4 is a face view of a disk, with a part broken away, and the holding device for the same.

ig. 5 is a side view of the disk to be ground and the supporting device therefor. Fig. 6 is a detail sectional view taken upon line 6-6ofFig.4.

As shown in said drawings, 5 designates a pedestal for a grinding machine provided with a head stockfi in whichis journaled a spindle or rotary arbor 7 carrying a flat faoedgrinding wheel or disk 8. Below the disk 8 is rigidly fixed a cylindrical. shaft 9 which extends outwardly from the pedestal parallel to the said spindle or arbor 7. Upon the said shaft '9 is mounted a hub 10 carrying an upright arm 11 upon the upper thereon, which the plane of the grinding 7, is formed with its side edges inwardly and Fig. 2 is a,

Specification of Letters Patent. Application filed January 29, 1909. Serial No.

Patented out. 19, 1909. 475,020.

5 end of which is 'carried a work table 12. Z' Said hub is adapted to be either turned upon 1 4 i I l l .16 of the vertical arm horizontal base a i 25 is pivoted tothe upper consists in the matters here-- particularly thereto.

base member said shaft, permitting the table to oscillate in a plane parallel to the grinding wheel or disk, or to be clamped or secured to the shaft useful Improvements in Grinding-Machines; in various ing a full, clear, and exact d 1 positions with respect to the grind- Upon one side faceof the hub 10 are two parallel vertical flanges 15, 15 adapted for sliding engagement with parallel edges 16,

11. Said arm is provided-with a longitudinal slot 17 through which pass cap screws 18 and 19, said cap screws extending into and having screwthreaded engagement with the hub 10 and serving to adjustably secure the said arm to the said hub.

The work table 12, which consists of a member 25 and a table top 26 having horizontally sliding engagement. therewith, ,is mounted upon the upper end of the vertical arm 11. The base member end of the arm 11 sons to swing on an axis parallel with the face of. the grinding disk and is thereby adapted to be tilted into positions of varying grmding wheel or disk. The b ase member 25 is narrower than the table top 26 and downwardly beveled giving dovetail form The side margins of the said base member engage the inner faces of two longitudinal flanges 27, 27 on the under surface of said table top 26. On the rear end of the table top 26, orthat end remote from theface of the grinding wheel or disk, is an arm .or extension 80 provided with laterally facing rack-teeth adapted to mesh with a gear pinion 31 mounted upon the rear end of the base member 25, which. latter is extended rearwardly beneath the path of the said arm 30. Said-pinion 31 is mounted or aifixedto the upper end of a vertical shaft 32 having be'ai ing inthe rear end of the said shaft 31 beneath the base member 25 is attached a horizontally swinging hand lever by means of which the table top 26 is ad vanced toward and retracted from the face of the grinding wheel or disk 8. At the 20. To the lower end of the outer end of the arm 30 on the table top is a. depending lug in which is mounted a micrometer screw 36 arranged in the path of and adapted 'for contact with the outer end of the base member 25. -Saidscrew .constitutes an adjustable stop for accurately table top. Supported in the said bearings 41 and 42 is a longitudinally arranged rotatable shaft 45 which is perpendicular to the face of the grinding wheel 8 and to the inner end of which is attached a disk holding plate 50 hereinafter referred to. To the outer end of the said shaft is attached a crank handle 47 by means of which the work may be rotated. The holding plate 50 is mounted upon the shaft 45 with its face in a plane parallel. with the working face of parallel with the holding plate 50 and with the working face. of the said the grinding disk 8.

The piece of work to be ground is indicated in the drawings by 51 and as therein shown has the form of a flat disk provided with a central circular aperture and a series of annularl arranged holes, such disk being like the see -droppmg disks used in the seeddropping mechanism of corn planters, Said disk 51 is so supported on or by the holding plate that its outer face, which is to be ground or finished, may be rotated in contact with the grinding wheel 8 and at the same time may be maintained in position generally rinding disk. For this purpose the said hoIding plate is provided with two sets of pins or lugs, the pins of the separate sets being designated by the reference numerals 52, 52, 52 and 53, 53, 53, respectively. The pins 52, 52 constitute the means by which the disk 51 is held from turning upon and caused to rotate with the plate 50 and will hereafter be referred to as the driving pins. The said driving pins are adapted to engage wit 1 the edges of any a erture, or with other holding edges or'shoul ers with which the disk to be ground may be provided. Said driving pins may be distributed over the face of the plate 50 in any suitable manner, depending upon the shape of the work to be ground or the location of the holding edges or shoulders thereon. Instead of the driving pins herein referred to there may be employed other parallel with the plane of rotation of the suitable holding and driving means, such as a magnetic clutch, or an expansion clutch when there. is a central, circular opening in the disk to'be ground. The pins 53, 53, 53 constitute bearing pins by means of which the disk 51 is retained in position generally grinding Wheel 8. The said bearing pins are three in number-- and are-arranged at equal distances apart upon the face of the late 50 and preferably at equal distances rom the axis of rotation of the said plate. The said bearing pins are somewhat shorter than theholding pins but of suflieient length for contact with the back of the disk 51 when it is in position for engagement with the holding pins. In case the driving pins engage with apertures extending through the disk or piece of work to be ground, as in the case of the seed-dropping disk illustrated, the bearing pins will be made of such length as to prevent said driving pins from projecting beyond the outer face of the disk, as clearly seen in Figs. 5 and 6.

The grinding attachment described is intended more particularly for grinding or finishing upon one side thereof disks or like objects (such as the seed-droppingdisk re ferred to) which are made of cast metal and are left rough or unfinished on their rear faces. Such a disk or object if rough or ir- I regular on its rear face could not be supported in the grinding operation by restin directly against the flat face of the wor: holding plate '50, because, by reason of roughness or irregularity of its rear face, the object would not come to firm bearing against the said plate and would be liable to tip or tilt in the grinding operation. The three backing pins, arranged as described, afford a three-point bearing against which the work rests in the grinding operation and by which the same will be firmly supported notwithstanding irregularity or roughness of its rear face; the object being held by said bearing pins in position generally parallel with the face of the grinding disk. The outer face of the object when so supported may not be exactly parallel with the grinding disk, but, as the result of the grinding operation, the finished surface formed thereon will be parallel with the face of the work holding plate and face, a fiat object or disk which has been left rough or unfinished on its rear face.

I claim as my invention 5- 1. In a disk grinding machine, the combination with a rotating grinding disk having a flat working face, and a rotative work holding shaft which is parallel with the axis of rotation of the grinding disk and is movable toward and away from the face of the same, of a work holder carried upon the end of the said shaft adjacent to the face of the grinding disk and provided with three backmg pins and with means adapted for driving engagement wi'th the work. 2. In a disk grnding machine, the combination with a rgitating grinding disk having a fiat wprkind; face, and a rotative work holdingshalft which is parallel with the axis of rotation of the grinding disk and is movas my invention I afiix my si ature in the able toward and away from the face of the resence of two witnesses, this 16th day of same, of a work holder carried upon the end an'uary A. D. 1909. e

of the work holding shaft adjacent to the JOHN MHLER, JR.

3 face of the grinding disk and provided with Witnesses:

a driving pin and with three backing pins. A. F. Sminmme, In testimony, that I claim the foregoing E. F. HANSEN. 

